Worldfire

Exile all permanents. Exile all cards from all hands and graveyards. Each player's life total becomes 1.

Marath, Will of the Wild

Marath, Will of the Wild enters with a number of +1/+1 counters on it equal to the amount of mana spent to cast it.
{X}, Remove X +1/+1 counters from Marath: Choose one —
• Put X +1/+1 counters on target creature. X can't be 0.
• Marath deals X damage to any target. X can't be 0.
• Create an X/X green Elemental creature token. X can't be 0.

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.